激光喷丸DP980高强钢诱导的残余应力分布特性  

Characteristics of Residual Stress Distribution on DP980 High Strength Steel Subjected to Laser Peening

作　　者：王作伟 崔凯 刘牧熙 Wang Zuowei;Cui Kai;Liu Muxi(Saic Volkswagen Automotive Yizheng Branch Co.,Ltd.,Yangzhou 225000)

机构地区：[1]上汽大众汽车有限公司仪征分公司,扬州225000

出　　处：《汽车工艺与材料》2024年第4期50-56,共7页Automobile Technology & Material

摘　　要：为研究激光喷丸后DP980高强钢的残余应力分布特性,建立有限元分析模型,分析不同激光喷丸次数对材料表面及深度方向的应力分布影响规律。开展不同激光喷丸次数的强化试验,并对试样进行残余应力检测,验证试验与模拟结果的一致性。通过对比激光喷丸前、后试样的表面粗糙度差异,发现激光喷丸后试样表面产生了塑性变形,并在表面形成均匀的残余压应力。在深度方向上,为达到材料内部应力平衡,试样芯部产生了低幅值的拉应力。随着激光喷丸次数的增加,材料表面诱导的残余应力幅值升高,产生更深的影响层。激光喷丸在材料表面诱导的残余压应力增加了零部件内部微裂纹的闭合力、延缓了裂纹扩展速率,可提高零部件的使用寿命及可靠性。In order to study the characteristics of residual stress distribution on DP980 high-strength steel treated by Laser Peening(LP),a finite element analysis model was established to analyze the influence of different LP times on the stress distribution both on the surface and in the depth of the material.Additionally,strenuous tests with different LP times were carried out,and the residual stress of samples was tested to verify the consistency of experiment and simulation results.By comparing the surface roughness of the samples before and after LP,it indicates that plastic deformation occurs on the sample surface,and a uniform residual stress distribution is generated on the surface after LP.In order to achieve the internal stress balance,a low-amplitude tensile stress is induced at the core of the sample along the depth direction.With the increase of LP times,the residual stress induced on the surface of sample rises,and a deeper influence layer is generated.In fact,the residual stress induced by LP on the material surface increases the micro-crack closure force inside the parts and then postpones the crack growth rate,thus improves the service life and reliability of parts effectively.

关 键 词：激光喷丸 高强钢 数值模拟 残余应力 

分 类 号：U465.1[一般工业技术—材料科学与工程]